Polystyrene multi-closure strip adapted for separation into individual closures



Jan. 5, 1965 F e PAXTON 3,164,250

POLYSTYRENE MuLTI cLosuRE STRIP ADAPTED FOR SEPARATION INTo INDIVIDUALCLOSURES Filed Nov. 22, 1963 3/ 30 3/ mg WJIIIIIIIIIM I aa F 1 2070 6.4X7/V INVENTOR ATTOAA/EV United States Patent 3,164,250 POLYSTYRENEMULTI CLOSURE STRI? ADAPTED FOR SEPARATIGN INTO IN- DIVIDUAL CLUSURESFloyd G. Paxton, Kwik Lok Corp, R0. Box 2098, Yakima, Wash. Filed Nov.22, 1963, Ser. No. 325,665 Claims. (Cl. 20656) This application is acontinuation in part of my copending application Serial No. 190,207,filed April 24, 1962, for a Multiple Closure Strip, said copendingapplication having been abandoned since the filing of the instantapplication.

This invention relates to closures formed of flat material such asextruded polystyrene and particularly to a multiclosure strip of suchmaterial.

Heretofore it has been common practice to form tickets, price tags, andthe like in strip form with a line of perforations provided at adjoiningedges of adjacent tickets in the strip so that one or more tickets canbe readily separated by tearing these from the strip along one of theselines of perforation. In some cases, cardboard tags united by webs havebeen provided in strip form for use in code-marking machines havingmeans for die-cutting said webs to separate any desired number of tagsfrom the strip.

For many years the use of sheet polystyrene closures for closing thenecks of polyethylene bags in which food and other products arepackaged, has been growing. The need has long existed for a better wayof feeding these closures to a bag closing station. Attempts to do thisby joining the closures integrally in a multi-closure strip have beendefeated by the fact that the peculiar characteristics of polystyrene inthe thickness (.032 inch) required for these closures, have renderedimpractical the tearing or severing of the strips to separate the latterinto individual closures. In the first place, insuificient room isavailable in machines provided for applying the closures to bags toaccommodate a die-cutting operation. In the second place, attempts topull the endmost closure from the strip by pulling apart the websconnecting adjacent closures resulted in each closure so separatedhaving one or more of said webs still integrally united therewith. Inother words the tendency was for each of the webs to be pulled free fromonly one of the adjacent closures it connected. These webs had sharpends which scratched the hands of a person removing the closure from abag as well as giving the closure a ragged appearance.

It is a primary object of the present invention to provide amulti-closure strip of the type above mentioned which does not require adie-cutting operation in separating individual closures from the stripin order to obtain relatively complete separation of each web from theclosures connected thereby.

Another object of the invention is to provide such a multi-closurestrip, the individual closures of which may be relatively completelyseparated from the strip by the mere applicationof a lateral pressurelocally against opposite edges of the strip.

The manner of accomplishing the foregoing objects as well as furtherobjects and advantages will be made manifest in the followingdescription taken in connection with the accompanying drawings in whichFIG. 1 is a perspective view of a preferred embodiment of themulti-closure strip of the present invention.

FIG. 2 is an enlarged detail view of the structure and the optimumdimensions of one of the closures of said strip and the frangible meansby which it is integrally united with adjacent closures in oppositedirections therefrom in said strip.

FIG. 3 is a transverse sectional view taken on the line 3-3 of FIG. 2.

FIG. 4 is an enlarged diagrammatic elevational view illustratingadjacent portions of a consecutive pair of closures in said closurestrip and showing how the application of two co-planar forces applied inopposite directions in the plane of said strip to opposite side edges ofsaid two closures simultaneously fractures the closure connecting websat their opposite ends within the areas in which said webs had beenunited with said closures, thereby completely separating said closuresfrom each other and from said webs.

FIG. 5 is a view similar to FIG. 1 illustrating in perspective amodified form of the multi-closure strip of the invention.

Referring specifically to the drawings and particularly to FIGS. 1, 2, 3and 4 the preferred embodiment of the invention disclosed thereincomprises a multi-closure strip 15 which is preferably formed from athin ilat strip of polystyrene or the like which is about .032 inch inthickness and /8 of an inch in width and is die-formed to produce insaid strip a consecutive series of closures 16 each of which has a heartshaped bag-neck-confining mouth 17 which is connected to one of theedges 18 of the closure by a narrow opening 19 having widely flaringlips 20. To complete the manufacture of the multi-closure strip 15, thedie-cutting operation cuts a notch 21 in strip side edge 18 and a notch22 from the opposite side edge 23 of said strip said notches beingarranged symmetrically relative to transverse aXes 24 which are equallyspaced from the transverse axes 2,5 of the bag-neck-confining mouths l7and openings 19. Simultaneously with the formation of notches 21 and 22,a transverse slot 30 is formed symmetrical with axis 24, this slotconstituting a rectangle having a dimension lengthwise of the strip of.0625 inch and having its ends closed by two webs 31, the length ofwhich is equal to the width of said slot, the transverse dimension ofwhich webs being .039 inch. The webs 31 are preferably uniform in widththroughout their length and inner portions of notches 21 and 22preferably have parallel walls 32 which are spaced apart the samedistance as the width of slot 30 and are in alignment with thetransverse walls of said slot. It is thus to be noted that all fourangles with which each of the Webs 31 meets the consecutive pair ofclosures 16 which are integrally joined by said webs are right angles.The significance of this will be pointed out hereinafter.

The polystyrene from which the multi-closure strip 15 is made isparticularly suitable because of the stifiness combined with flexibilitywhich it gives to the closures 16 thus adapting them to be applied andremoved from a bag many times without injuring the closure. I havediscovered that it is'highly desirable to make the webs 31 longer thanthey are wide and at the same time to make them relatively narrow. Thishas a twofold result of increasing the flexibility of these webs topermit them to resist crystalization under the flexing of themulti-closure strip when coiling this for transportation and uncoilingit for use, and has also offered a solution to the problem of separatingthe closures from each other in the very narrow space ailorded for thisin the closure applying machine while at the same time assuring thatnone of the webs 31 remain integrally united with a separated closure.

This solution arises from the fact that the endmost closure 16 ofclosure strip 15 above described may be readily separated from the stripby the operation illustrated in FIG. 4. Here I see the strip 15 providedwith side edge guide plates 33 and 34 and Witha shiftable finger 35 forapplying pressure to the left edge of the lowermost closure 16 when itcomes time to separate this from the balance of the strip. The rightguide plate 34 supports the next closure thereahove to prevent thatclosure being moved laterally in response to the pressure finger 35 sothat shifting of this finger as shown in FIG. 4 in a horizontal.direction against the left edge of the lower closure 16 tends to rotatethe webs 31 about axes normal respectively to their centers and to theplane of the closure strip thereby fracturing opposite ends of the webs31 in the planes in which they previously were integrally connected tothese two closures. These four fractures occur simultaneously andpractically completely separate the webs from the closures althoughslightly rough spots are formed on the edges of the closures where thesewere formerly united with said Webs.

I have also discovered that by providing the parallel walls 32 at theinner ends of notches '21 and 22 just outside of and adjacent to thewebs 31 substantially improves the smoothness of the separation of thewebs 31 from the closure 16 in the operation illustrated in PEG. 4.

Before developing closure strip 15, a closure strip 36 shown in FIG. wasdeveloped by me in which webs 37 are provided which are locatedoutwardly adjacent to widely diverging edges 38 of notches 39 and 59formed in the left and right edges respectively of closure strip 36. f/hen performing the operation shown in FIG. 4 on closure strip 36,simultaneous fractures at opposite ends of both of the webs 37 occuralthough there is a tendency to form a sharp corner between the fractureareas at the ends of Webs 37 and an adjacent edge 38 of one of thenotches 39 and 40. It is preferable therefore to place the websconnecting consecutive closures inwardly from the flaring edges ofnotches 21 and 22, as in multi-closure trip 15, so as to eliminate thissharpness.

It being essential to the proper operation or the present invention thateach closure 16 when it becomes the lowermost closure in the stripresist buckling when the finger 35 is applied transversely to one edgeof the closure in order to shift this closure laterally and thusseparate it from the next closure thereabove, the use of polystyrene asthe material from which the closure strip is made attains significancein that the characteristics of this material of stiffness andfrangi-bility not only imparts to the closure a high resistance tobuckling when subjected to such a transverse force but also renders thewebs 31 when made with sufiiciently small cross section, readilyfrangible simultaneously at their opposite ends as a result of the forceapplied by finger 35 transversely to the lowermost closure andaccomplishes this before the pressure from finger 35 against the closurereaches a point which would cause a buckling of the closure which wouldinterfere with the simultaneous rotation of the webs with resultantfracturing of these along the lines of their union with the two closuresconnected thereby.

When the multi-closure strip is made with the dimensions'shownwon FIGS.2 and 3 of the drawings, the simultaneous separation of the webs 31 fromthe two closures joined thereby as shown in PEG. 4 takes place inresponse to a pressure applied to the lowermost closure by the finger 35of approximately 4 lbs. This pressure is only about two-thirds of thepressure which would have to be'applied edgewise in the plane "of thefinger 35 to the lowermost closure and in opposite directions inwardlyfrom opposite side edges thereof in order to buckle this closure andproduce a vertical straight fracture leading from the bag confiningmouth 17 to the upper edge 30 of said closure; 7

With this margin of strength built into the individual l /hile only onepreferred form of the present invention and one modified form thereofhave been disclosed herein, it is understood that various modificationsand changes may be made in these without departing from the spirit ofthe invention or the scope of the appended claims.

The claims are:

1. In a multi-closure strip, wherein the closures each may have a bagconfining mouth and a narrow opening located in a longitudinal side edgethereof and communicating with said mouth for admitting a bag neck intothe latter; the structure comprising: a multiple of closures oftransversely stiff, thin, sheet material comprising polystyrene or thelike, arranged consecutively with their transverse edges in closelyspaced relation; and web means integrally connecting with eachconsecutive pair of do sures in frangible areas of union located betweenopposite ends of said web means and said closely spaced edges of saidconsecutive closures, said frangible areas being spaced far enough apartlength-wise of said strip and being sufiicie-ntly restricted in thecross sectional dimension thereof measured transversely of said strip,that compressive forces applied in the plane of said strip from oppositedirections respectively to said consecutive closures and through saidclosures to opposite ends of said web means without causing saidclosures to buckle, will cause the material of said strip tosubstantially simultaneously crack in said frangible areas of union atthe opposite ends of said web means and thus separate said web meansfrom said closures and said closures from each other.

2. In a multi-closure strip, the structure recited in claim 1, whereinthe web means integrally connecting each consecutive pair of closures insaid strip comprises a pair of transversely spaced webs.

3. In a multi-closure strip, the structure recited in claim 2 whereinportions of each transverse edge of a closure, lying immediatelyadjacent to and on opposite sides of the area of union between said edgeand one of said webs, are transversely aligned and form right angleswith said web.

4. In a multi-closure strip, the structure recited in claim 2, whreinthe length of each of said webs, which is the distance measuredlengthwise of said strip between said areas of union at the ends of saidweb, is substantially greater than the width of one of said areas ofunion which is the dimension thereof measured transversely of saidstrip.

5. In a multi-closure strip, the structure recited in claim 4, whereinsaid Width of said area of union at each end of each web isapproximately .039 inch, the length of said web is approximately .0625inch and the thickness of said strip is approximately .032 inch.

References Cited by the Examiner UNITED STATES PATENTS 2,705,100 3/55Paxton et al 53-138 2,855,647 10/58 Smith 24-305 2,884,123 4/59 Dann etal. 206-43 2,907,586 10/59 Paxton et a1. 229-65 3,022,571 2/62 Niedecker29-1935 3,061,983 11/62 Trmin 53-138 3,072,770 1/63 Goodridge 29-413FOREIGN PATENTS 232,093 1/6 1 Australia.

DONLEY I. STOCKING, Primary Examiner.

1. IN A MULTI-CLOSURE STRIP, WHEREIN THE CLOSURES EACH MAY HAVE A BAGCONFINING MOUTH AND A NARROW OPENING LOCATED IN A LONGITUDINAL SIDE EDGETHEREOF AND COMMUNICATING WITH SAID MOUTH FOR ADMITTING A BAG NECK INTOTHE LATTER; THE STRUCTURE COMPRISING: A MULTIPLE OF CLOSURES OFTRANSVERSELY STIFF, THIN, SHEET MATERIAL COMPRISING POLYSTYRENE OR THELIKE, ARRANGED CONSECUTIVELY WITH THEIR TRANSVERSE EDGES IN CLOSELYSPACED RELATION; AND WEB MEANS INTEGRALLY CONNECTING WITH EACHCONSECUTIVE PAIR OF CLOSURES IN FRANGIBLE AREAS OF UNION LOCATED BETWEENOPPOSITE ENDS OF SAID WEB MEANS AND SAID CLOSELY SPACED EDGES OF SAIDCONSECUTIVE CLOSURES, SAID FRANGIBLE AREAS BEING SPACED FAR ENOUGH APARTLENGTH-WISE OF SAID STRIP AND BEING SUFFICIENTLY RESTRICTED IN THE CROSSSECTIONAL DIMENSION THEREOF MEASURED TRANSVERSELY OF SAID STRIP, THATCOMPRESSIVE FORCES APPLIED IN THE PLANE OF SAID STRIP FROM OPPOSITEDIRECTIONS RESPECTIVELY TO SAID CONSECUTIVE CLOSURES AND THROUGH SAIDCLOSURES TO OPPOSITE ENDS OF SAID WEB MEANS WITHOUT CAUSING SAIDCLOSURES TO BUCKLE, WILL CAUSE THE MATERIAL OF SAID STRIP TOSUBSTANTIALLY SIMULTANEOUSLY CRACK IN SAID FRANGIBLE AREAS OF UNION ATTHE OPPOSITE ENDS OF SAID WEB MEANS AND THUS SEPARATE SAID WEB MEANSFROM SAID CLOSURES AND SAID CLOSURES FROM EACH OTHER.